The present invention relates to an apparatus and method for collecting samples of smoke components from predetermined segments of a smoke stream during a predetermined time interval.
Considerable attention has been given to the study of specific compounds of the mainstream smoke of smoking articles. Various techniques have been suggested for measuring the yields of the mainstream smoke compounds. Among these techniques are assaying methods such as gas chromatography, radioisotope labelling and the like. These techniques, however, provide information about the specific overall composition of the smoke rather than the concentration of a particular component during a predetermined time interval within each individual puff.
A technique utilizing a smoking machine which separates the particulates from sequential puffs of a cigarette has been proposed in U.S. Pat. No. 3,433,054 to Mutter. The smoking machine utilizes a series of cigarettes mounted on a primary wheel and a series of filters mounted on a secondary wheel. The two wheels are rotated in a manner so that the first puff from each individual cigarette is drawn through a first filter unit, a second puff is taken from the individual cigarette and drawn through a second filter unit, and so on, thereby providing for collection of drawn smoke components from each puff. U.S. Pat. No. 3,433,054 to Mutter does not suggest collecting components at specified times during an individual puff.
A technique for measuring smoke components at specified times during a puff has been suggested by Ceschini et al in Beitr. Tabakforsch Volume 6, page 378-381 (1976). The concentration of mainstream smoke components is studied by testing the various thirds composition of a single puff, rather than testing the composition of the entire continuous puff.
U.S. Pat. No. 4,204,550 to Newman et al proposes an apparatus for collecting smoke components within a puff. The apparatus collects the particulates from each puff as an arcuate band on a filter mounted so as to rotate at a controlled azimuthal speed. However, it is expected that the cyclical path of travel results in a radially nonuniform distribution inasmuch as the inner portion of the arcuate band may have a heavier deposition of particulates than the outer portion of the arcuate band. Analysis of the collected components can be complicated by the need to take account of the preferential non-uniform distribution effect.
It would be desirable to provide an apparatus and method for collecting smoke components from predetermined segments of the individual puffs during a predetermined time interval.